1. Field of the Invention
The present invention relates generally to motor vehicle brake lights and more specifically it relates to an emergency deceleration warning light device. Even more specifically, it relates to an emergency brake light device that responds to the pressure within the brake cylinder and, when a predetermined threshold has been reached, activates a time delay that in turn activates a flashing, distinctive light on the rear deck of the vehicle to warn a following driver that a large change in velocity is occurring. More generally, the present invention could be used in a wide variety of applications wherein the braking system has a hydraulic cylinder to transmit the brake pedal force to the various brake drums. The variously colored warning lights could be mounted on a motorcycle, for instance, or on myriad types of construction or earthmoving equipment.
Thus it can be seen that the potential fields of use for this invention are myriad and the particular preferred embodiment described herein is in no way meant to limit the use of the invention to the particular field chosen for exposition of the details of the invention.
A comprehensive listing of all the possible fields to which this invention may be applied is limited only by the imagination and is therefore not provided herein. Some of the more obvious applications are mentioned herein in the interest of providing a full and complete disclosure of the unique properties of this previously unknown general purpose article of manufacture. It is to be understood from the outset that the scope of this invention is not limited to these fields or to the specific examples of potential uses presented hereinafter.
2. Description of the Prior Art
Rear end collisions are one of the most common traffic incidents. Many of them are caused simply because the driver following a decelerating vehicle cannot gauge the amount of .DELTA.V being dropped. The present invention is directed towards addressing this problem by providing a clear indication on the rear of the vehicle that a large amount of braking force is being applied, thus allowing the following driver to react. A number of U.S. Patents relate to this field and they are discussed hereinafter:
First is U.S. Pat. No. 3,708,782 issued on Jan. 2, 1973 to Takakazu Mori. This discloses an abrupt brake application indicator wherein a pair of switches, the first activated by minimal movement of the brake pedal and the second when a predetermined amount of movement or predetermined amount of hydraulic pressure, are activated in turn. A time threshold is maintained and the activation of the second switch is compared to this threshold. If the second switch activation falls within the threshold, a second lamp, increasing the brightness of the brake light, is turned on. Alternatively, a single filament lamp may be supplied with additional voltage or a flasher is activated. This is dissimilar from the present invention in that there is no showing of the contrasting color warning light that makes the present invention a more attention drawing warning system.
Next is U.S. Pat. No. 3,827,522 issued on Aug. 6, 1974 to Kenneth M. Krause. This discloses a fluid pressure actuated brake light switch wherein a piston and switch plunger activate the taillights of a vehicle whenever the pressure in a relief valve manifold of the hydraulic system exceeds a predetermined level. Unlike the present invention, there is no teaching of the time delay or the contrasting warning flasher coloring.
U.S. Pat. No. 3,939,316 issued on Feb. 17, 1976 to Edward J. Stropkay discloses a panic stoplight system with a fluid pressure switching device. In this device, the fluid pressure activates switches to flash warning lights. Controlling the bleed rate of the fluid out of the actuating chamber allows the warning lights to keep flashing even after the panic braking has stopped. This is clearly unlike the present invention in that there is no time delay before the warning lights are activated and neither is the contrasting color of the warning light disclosed.
Next is U.S. Pat. No. 4,231,013 issued on Oct. 28, 1980 to William H. Freeman et al. This is a vehicle brake light illumination system. The brightness of the brake light varies according to the pressure in the brake fluid line. This is unlike the present invention in that no timing delay is disclosed for the warning light.
U.S. Pat. No. 4,920,330 issued on Apr. 24, 1990 to Lisio Plozner discloses a mercury inertial transducer with a light emitting indicator. Though Plozner teaches a central light located on the rear deck of a motor vehicle that has a contrasting warning color, the light does not flash on and off as in the present invention, nor is a time delay taught.
Lastly, U.S. Pat. No. 5,150,098 issued on Sep. 22, 1992 to Robert Rakow discloses a brake signaling system. A sequential series of lights is taught, with the lights activated one after the other as the pressure within the hydraulic system increases. This is unlike the present invention in that there is no teaching of either the time delay, the flashing of the warning light when a large amount of pressure is applied to the brake, nor the contrasting color of the warning light.
None of the above inventions and patents, taken either singly or in combination, is seen to describe the instant invention as claimed.